Concept:G. Stanley Hall, known as the father of adolescent psychology, focused on the "storm and stress" period of adolescence.
Explanation:Hall's theory primarily describes adolescence as a time of emotional upheaval, rapid changes, and identity search.
He defined adolescence in his 1904 text and highlighted it as a period of vulnerability and inconsistent behavior.
This matches the study of adolescent psychology, not intelligence, motivation, or value development.
Answer:D. Psychology of Adolescents